Honda Hrb 425c Push Mower Not Working

Here we have a Honda HRB425c 4stroke petrol lawn mower with two grass boxes. Mower was built in 1999 and was working perfectly last year. This year I came to use it and it wouldn t start. Changed the air filter, changed the fuel, changed the spark plug even cleaned out the carburettor but I still can t get it fire. Madam got fed up with waiting for the grass to be cut and bought a new one. The mower is in good condition, blade is slightly rusty and has a few dinks in it. There are a few scratches around it and the second grass box has a crease/tear in the back where it has sat in the shed. Engine turns over easily, it just won t fire - very frustrating. I have reached the limit of my ability to repair it, I suspect that it will be an easy repair for someone who knows more than I do. Sticker on the front says HRB425c but the plate on it says it is a type HRB425CSOE. In case it helps Serial No is MZCF8010077. Mower is the type where the engine drives the wheels and it has 5 height settings for the cut. Cash on collection is preferred but if you do want it shipped it will cost £74.00 - this is only to the postcodes shown on interparcel.com as UK Mainland. If you are outside this area give me your postcode and I will give you a price. If you have any questions please ask, if you want to view the item is in Sevenoaks.